A New Impregnated Dispenser Cathode

作者：Yin Shengyin^*; Zhang Zhaochuan; Peng Zhen; Zheng Qiang; Wang Yu

来源：IEEE Transactions on Electron Devices, 2013, 60(12): 4258-4262.

DOI：10.1109/TED.2013.2287729

• Ba
• emission performance
• impregnated scandate cathode
• Sr

To meet the demand of terahertz devices, we develop a new type impregnated dispenser cathode. This cathode is impregnated with an active substance with molar ratio of 26BaO center dot 29SrO center dot 8Sc(2)O(3)center dot 7CaO center dot Al2O3. We test its emission performance, practical work function distribution, and surface composition, and analyze the mechanism of the high emission performance. At 1100 degrees C-B, the pulse current density is 171.6 +/- 2.8 A/cm(2), 5.4 times of that of an M-type cathode. The peak work function of Miram curve is similar to 1.570 eV. Ba, Sc, Ca, Al, and O atoms are detected on most surfaces of tungsten grains. It is proposed that the Ba-Sc-Al-Ca-O layer on the surface of the cathode is responsible for the excellent emission performance.

• 出版日期2013-12
• 单位中国科学院大学